1. Technical Field
The present invention relates to an image forming apparatus including a plurality of developers storing toner therein and an image forming method thereof.
2. Related Art
In electrophotographic image forming apparatus, such as printers, copiers and facsimiles, which form images using toner, a proposal has been made such that plural developers each storing therein a toner of the same color are mounted in the apparatus for use in the apparatus. An image recording apparatus disclosed in JP-A-2003-316106 (equivalent to an “image forming apparatus” herein), for example, is an image recording apparatus which is capable of mounting plural developers, so that the apparatus may be used not only as a color printer when mounted with developers storing therein toners of different colors but also as a monochromatic printer when mounted with developers each storing therein a toner of the same color.
In this image recording apparatus, a developer mounted to a predetermined position is used preferentially. However, when the residual quantity of toner in the developer is decreased to a predetermined level, the developer is switched to another developer. According to another mode of the image recording apparatus, in a case where there are a plural number of usable developers, one of the developers that was mounted at the earliest point in time is used preferentially.